Melbourne's Metro Trains put vandals on notice over graffiti

Melbourne Metro has put vandals on notice – declaring it will adopt a New York subway-style “zero tolerance” approach to graffiti.

Under the tough new stance, trains will be pulled out of service the moment vandalism is spotted, even if it means disrupting peak hour commutes.

Rampant vandalism has been a serious – and unsightly – issue on the rail network for years, but over the next four months 474 X'Trapolis carriages will have their windows replaced, walls cleaned and polished and even get a deep clean.

Vandalised train carriages will be a thing of the past. (9NEWS)

The cleanup operation comes with a price tag of $2 million, but Metro believes it is money well spent.

“We’re going to get it off (graffiti) and we’re going to keep it off,” Metro Trains CEO Andrew Lezala said.

Metro’s new zero tolerance approach to graffiti will see trains pulled off the line and sent back to the depot as soon as an issue is spotted.

The tactic is credited with helping transform the New York subway from crime and grime in the 1980s to today’s shiny silver service.